Field of the Invention
The present invention relates to a golf club shaft.
Description of the Related Art
A so-called carbon shaft has been known as a golf club shaft. A sheetwinding method has been known as a method for manufacturing the carbon shaft.
A prepreg includes a matrix resin and a fiber. Many types of prepregs exist. A plurality of prepregs having different resin contents have been known. In the present application, the prepreg is also referred to as a prepreg sheet or a sheet.
In the sheetwinding method, the type of a sheet, the disposal of the sheet, and the orientation of a fiber can be selected. A sheet constitution is designed corresponding to desired characteristics of a shaft.
Japanese Patent No. 4112722 discloses a golf club shaft including a circumferential reinforcing fiber layer having a total thickness set to a range of 10 to 30% based on the total thickness of the shaft.